I installed Linux Mint 64-bit recently but it freezes up all the time. Not only that, but Grub wouldn't detect Windows.

I thought it was just an issue with Linux Mint so I booted into Ubuntu - however that froze up as well. I downloaded Fedora to replace Linux Mint with, but that also freezes up.

I finally gave up trying to repair Grub, burning a supergrub grub2 disk and using that to boot into Windows. Windows now freezes up as well. I installed a new copy of Windows on a different drive but to no avail.

Right before all this started my computer was running very smoothly. I am wondering if the installation of Linux Mint, the reinstallation of Grub, or me messing with the BIOS (when I was attempting to repair Grub) could have done something drastic enough that everything is slow now? I realize that computers get gradually slower over time, but this was in no way gradual and it happened directly after the installation of Linux Mint.

There are two ways installing a new OS can slow things down. Disk drives vary in speed based on the section of the disk you're accessing, with the fastest part normally located at the logical beginning of the drive. If you move a partition to a later section of the drive, it will probably be slower there.

It's also possible to slow your computer a bit if the original partitions were aligned well with the filesystem boundaries, while they aren't anymore. Windows and Linux handle partitioning a bit differently by default, and getting that consistent is a challenge.

None of this will result in random freezing though, just slower performance. That's more likely to be a hardware problem. You should try using smartmontools while in Linux to look for hard drive problems: check the error logs, see if there is a high reallocated sector count (that suggests parts of the drive are failing), and trigger a self-test.

And the Mint installer should have memtest86 too, which will stress your CPU, memory, and motherboard. If memtest86 freezes the same way, you'll have isolated the problem as being unrelated to the hard drive changes--once it boots, it runs completely from memory.

Oh, and first thing: make sure you have a good backup of your important files!

Well to be honest I went in to BIOS and reset it to optimal defaults (or whatever its called) and installed 64 bit windows and now things are going smoothly. Somehow, either me or Linux mint, messed up my BIOS settings.

Edit: I eat my words. Now things are once again slow. I tried the Memory check and error checking, but everything seemed to be going fine with those

Edit: Well, after several sessions of windows update, Windows is once again going fine. I'll leave this open for a couple days to make sure it continues to do so.